Modern motor vehicles nowadays have devices, actuated by external force or driven by motor, for moving (opening or closing) windows. Such devices comprise a motor unit as adjusting motor, which are provided in a motor vehicle door by means of a transmission mechanism and corresponding cables for moving the windows. The assembly process in motor vehicles generally requires a modular configuration of the individual components, as in a window lifter. One module is formed by the motor unit which, within a housing, can have both an electric motor and also a corresponding transmission, wherein a second module, which can be designed as a plug-in module, can be connected to the module of the motor unit in order to provide current and to control the electric motor. To supply the motor with electrical energy, the plug-in module has a plug with corresponding motor contacts which, when the plug-in module is inserted into the housing of the motor module, are connected to complementary electrical contacts of the motor unit. Furthermore, electrical energy or electrical current must also be fed to the plug-in module for transmission to the motor. However, this proves very difficult to do on account of the generally confined space available within a vehicle door.